[Cython] New idea for C++ stack allocation

[Robert Bradshaw]

On Apr 27, 2009, at 11:57 PM, Dag Sverre Seljebotn wrote:

> I got another idea for how using C++ objects without no-arg  
> constructors
> could work. It means enforcing C++ variable scoping through compile- 
> time
> errors, but keeping Python syntax.

I think for our first pass at least, we should allocate everything on  
the heap. We could then try to (transparently?) move things to the  
stack when we can (this would have implications for passing things  
around though).

> The transform necesarry to enforce these rules should not be too
> complicated. I don't think we need full analysis, just track  
> assignments
> and deletions and usages on a per-name basis.
>
> Finally, the C++ output is made by adding a block, i.e.
>
>    cdef CppObject obj
>    print 1
>    obj = bar
>    obj.func()
>    del obj
>    print 2
>
> Results in
>
>    print 1
>    {
>      CppObject obj = bar;
>      obj.func()
>    } # del
>    print 2

What about

cdef CppObject a, b
a = bar
b = bar
del a
del b

?

- Robert